Leaning out of a sudden

s300 and SManager software questions & answers
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Javcolin
Posts: 63
Joined: Sun Apr 01, 2007 9:47 pm

Leaning out of a sudden

Post by Javcolin »

Hi,

I encountered a problem that doesn't seem to make much sense to me,

I tuned my CRX LS Vtec Turbo low cam fuel and ignition map all good. So Opened up Vtec to tune high cam fuel. on waste gate spring around 7 psi all good hit my AFR Target 11.5 so then I proceed to enable boost control and set to 30% and reached 10 PSI so after a couple of pulls nailed my target AFR.

So then I wanted more boost so I incresed PWM to 40% did a pull and out of a sudden after vtec kicked in car was sort of chocking so let the gas off, and reviewed my datalog and noticed that my AFR went from being @ 11.5 to 13's climbing to 15's or so. with no other change to the previous run other than jumping from 30% to 40% PWM duty. I did tried 35% with same result leaning out. went back to my 30% map and car pushed 10 psi as previosly did.

But with both runs at 35 and 40% PWM boost went to 7 - 8 PSI max before droping gradually until I lift the gas pedal.

Things I have done to correct the problem.

Replaced my walbro 450 with another brand new 450 LPH also changed with brand new fue pump filter
Replaced the relay for the upgraded wiring to the pump
Cleaned my Fuel filter element
Replaced my FPR with an aeromotive

Fuel lines are -8 feed and -6 returned for e85 (currently running on pump gas)

I haven't checked the injectors yet. but other than that I have no Idea what else to do.

What makes no sense to me is that the only change from running well at 11.5 ARF to going really lean 13's 14's and climbing up real quick is the solenoid valve duty cycle. but on both runs never exceed 10 psi of boost that I made at 30% PWM. I would understand if it made 15 or 20 PSI and lean out a bit due to making more power but that is not the case.

I'm Using Hondata V3 Smanager 2.7.5.0

Attach calibration and both datalogs 10 psi one is with 30% PWM 40% one is the one with either 35 0r 40% PWM can't remember but both did the same exact thing.

Any thing i could check to see why is doing this?
Attachments
40% PWM.s3d
(32.25 KiB) Downloaded 132 times
10 psi.s3d
(280.88 KiB) Downloaded 132 times
CRX Base Map 37_10 psi 30% pwm.skl
(48.62 KiB) Downloaded 138 times
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Spunkster
Site Admin
Posts: 22741
Joined: Fri Sep 20, 2002 5:06 pm
Location: Hondata

Re: Leaning out of a sudden

Post by Spunkster »

Your boost is dropping off significantly at about 5200 RPM. So it is reading from different area on the table.
Javcolin
Posts: 63
Joined: Sun Apr 01, 2007 9:47 pm

Re: Leaning out of a sudden

Post by Javcolin »

Spunkster,

I noticed that, but I think the boost is dropping due to lean condition and the engine chocking and this lean condition happens at different RPM sometimes as early as 4800 rpm and some other around 5500 rpm.

I can see that reads in a different part of the map but those areas were tuned previosuly so if it drops to those areas it should still within the AFR target right? I tuned from 4500 up on waste gate spring and up to 10 psi

I have also tried adding fuel at those lean areas as much as 30% at this point the 3-d lines goes really high, yet still showing lean condition.

I will retune the lowere RPM areas on WG spring rate and will see if this condition improves.

Thanks
DaX
Posts: 654
Joined: Tue Mar 18, 2003 3:48 pm

Re: Leaning out of a sudden

Post by DaX »

My money is on the injectors being the issue. Spend the money and have them cleaned and flow tested before banging your head against the wall any further.
Javcolin
Posts: 63
Joined: Sun Apr 01, 2007 9:47 pm

Re: Leaning out of a sudden

Post by Javcolin »

DaX wrote: Thu Aug 13, 2020 4:21 pm My money is on the injectors being the issue. Spend the money and have them cleaned and flow tested before banging your head against the wall any further.
Sorry for the late Update, You were right on the money, My brand new DW injectors were bad, I sent them back to them to have them tested and they came back to me saying that 1 of tem was flowing 300cc less and other one was flowing 100cc higher making them anbalanced, I'm using 2000cc Bosch with no issues time to continue with the tune,
DaX
Posts: 654
Joined: Tue Mar 18, 2003 3:48 pm

Re: Leaning out of a sudden

Post by DaX »

Javcolin wrote: Fri Dec 18, 2020 11:07 pm
DaX wrote: Thu Aug 13, 2020 4:21 pm My money is on the injectors being the issue. Spend the money and have them cleaned and flow tested before banging your head against the wall any further.
Sorry for the late Update, You were right on the money, My brand new DW injectors were bad, I sent them back to them to have them tested and they came back to me saying that 1 of tem was flowing 300cc less and other one was flowing 100cc higher making them anbalanced, I'm using 2000cc Bosch with no issues time to continue with the tune,
Thanks for following back up, and glad you got it fixed!
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